Neuromuscular electrical stimulation, muscle mass, and physical function decline in the early phase after living donor liver transplantation.

This study aims to investigate the effects of neuromuscular electrical stimulation (NMES) in addition to conventional early mobilization in the early postoperative period after living donor liver transplantation (LTx) on body composition and physical function. This was a retrospective single-center cohort study. Adult subjects who were admitted for living donor LTx from 2018 to 2023 were included in the analysis. After April 2020, patients underwent 4 weeks of NMES in addition to conventional rehabilitation. The skeletal muscle mass index, body cell mass, and physical function, including the 6-minute walking distance, were assessed before surgery and at discharge, and changes in these outcomes were compared before and after the introduction of NMES. Sixty-one patients were in the NMES group, and 53 patients before the introduction of NMES were in the control group. ANCOVA with etiology, obstructive ventilatory impairment, Child-Pugh classification, and initial body composition value as covariates demonstrated that there was a significantly smaller decline of body cell mass (-2.9±2.7 kg vs. -4.4±2.7 kg, p = 0.01), as well as of the skeletal muscle mass index (-0.78±0.73 kg/m2 vs. -1.29±1.21 kg/m2, p = 0.04), from baseline to discharge in the NMES group than in the control group; thus, the decline after surgery was suppressed in the NMES group. Four weeks of NMES, in addition to conventional rehabilitation in the early period after LTx, may attenuate the deterioration of muscle mass. It is suggested that NMES is an option for developing optimized rehabilitation programs in the acute postoperative period after LTx.

Definition, diagnosis, and treatment of respiratory sarcopenia.

PURPOSE OF REVIEW: Skeletal muscle weakness and wasting also occurs in the respiratory muscles, called respiratory sarcopenia. Respiratory sarcopenia may lead to worse clinical indicators and outcomes. We present a novel definition and diagnostic criteria for respiratory sarcopenia, summarize recent reports on the association between respiratory sarcopenia, physical and nutritional status, and clinical outcomes, and provide suggestions for the prevention and treatment of respiratory sarcopenia. RECENT FINDINGS: Recently, a novel definition and diagnostic criteria for respiratory sarcopenia have been prepared. Respiratory sarcopenia is defined as a condition in which there is both low respiratory muscle strength and low respiratory muscle mass. Respiratory muscle strength, respiratory muscle mass, and appendicular skeletal muscle mass are used to diagnose respiratory sarcopenia. Currently, it is challenging to definitively diagnose respiratory sarcopenia due to the difficulty in accurately determining low respiratory muscle mass. Decreased respiratory muscle strength and respiratory muscle mass are associated with lower physical and nutritional status and poorer clinical outcomes. Exercise interventions, especially respiratory muscle training, nutritional interventions, and their combinations may effectively treat respiratory sarcopenia. Preventive interventions for respiratory sarcopenia are unclear. SUMMARY: The novel definition and diagnostic criteria will contribute to promoting the assessment and intervention of respiratory sarcopenia.

Relationship Between Physical Activity and Estimated Glomerular Filtration Rate in Renal Transplant Recipients: A Cross-sectional Study Analyzing Isotemporal Substitution Model.

OBJECTIVES: Successful renal transplantation reduces mortality rates. However, the decline in the estimated glomerular filtration rate (eGFR) after transplantation is strongly associated with premature mortality in renal transplant recipients (RTRs). Physical activity (PA) is a modifiable lifestyle factor with the potential to maintain or improve eGFR. However, the effects of the type or intensity of PA and sedentary behavior (SB) on eGFR in RTRs remain unclear. The purpose of this study was to clarify the association between accelerometry-measured PA and SB and eGFR in RTRs using isotemporal substitution (IS) analysis. METHODS: A total of 82 renal transplant outpatients participated in this cross-sectional study, of which 65 (average age, 56.9 years; average time post-transplant, 83.0 months) were finally analyzed. All RTRs wore a triaxial accelerometer to measure PA for 7 consecutive days. The measured PA was classified based on intensity into light PA, moderate-to-vigorous PA (MVPA), and SB. The association of each type of PA with eGFR was examined using multi-regression analyses of single-factor, partition, and IS models. The IS model was applied to examine the estimated effects of substituting 30 minutes of SB with an equal amount of time of light PA or MVPA on eGFR. RESULTS: The partition model showed that MVPA was an independent explanatory variable for eGFR (ß = 5.503; P < .05), and the IS model identified that the substitution of time spent in SB with MVPA led to improvements in eGFR (ß = 5.902; P < .05). CONCLUSIONS: The present study suggests that MVPA has an independent and positive association with eGFR, and replacing 30 minutes of SB with MVPA after renal transplantation might lead to the maintenance or improvement of eGFR in RTRs.

Predictors of Functional Decline in Activities of Daily Living at Discharge in Patients After Cardiovascular Surgery.

BACKGROUND: This study aimed to investigate the trajectory of functional recovery of activities of daily living (ADL) from the time of admission up to hospital discharge, and explored which preoperative and postoperative variables were independently associated with functional decline in ADL at discharge of patients after cardiovascular surgery.Methods and Results:In this observational study, we evaluated ADL preoperatively and at discharge using the Functional Independence Measure (FIM) in patients after cardiovascular surgery. Functional decline in ADL was defined as scoring 1-5 on any one of the FIM items at discharge. Multiple logistic regression was performed to predict the functional decline in ADL at discharge. We found that 18.8% of elective cardiovascular surgery patients suffered from decreased ADL at discharge. The Mini-Mental State Examination (odds ratio (OR): 0.573, 95% confidence interval (CI): 0.420-0.783), gait speed (OR: 0.032, 95% CI: 0.003-0.304) and initiation of walking around the bed (OR: 1.277, 95% CI: 1.103-1.480) were independently associated with decreased ADL at discharge. CONCLUSIONS: A functional decline in ADL at discharge can be predicted using preoperative measures of cognitive function, preoperative gait speed and postoperative day of initiation of walking. These results show that preoperative cognitive screening and gait speed assessments can be used to identify patients who might require careful postoperative planning, and for whom early postoperative rehabilitation is needed to prevent serious functional ADL deficits.

Determinants of Health-Related Quality of Life and Physical Performance-Based Components of Frailty in Patients Undergoing Hemodialysis.

OBJECTIVES: Health-related quality of life (HRQoL) measures capture the patient's experience of the burden of chronic disease and are strongly associated with adverse health-related outcomes across multiple populations. The SF-36 score is the most widely used HRQoL measure among patients with end-stage renal disease. Current understanding of determinants of the physical component summary (PCS) and the mental component summary (MCS) and their association with objectively measured physical performance and activity is limited. METHODS: As an index of HRQoL, we prospectively examined the association of SF-36 and its component scores with physical function among 155 incident dialysis patients from the Hemodialysis Center. We investigated associations of HRQoL with the physical performance-based components of the frailty using multivariate linear and logistic regression after adjustment for confounders. Impaired physical performance was defined as having either slow usual gait speed or weak handgrip strength based on standardized and validated criteria derived from a large cohort study of older adults. RESULTS: The patients had a mean age of 65 ± 11 years, and 52.3% were male. After adjusting confounders, lower PCS was independently associated with decreased physical performance and reduced physical activity, but MCS was not associated. Among the PCS subscales, only physical functioning 10 (PF-10) was consistently associated with outcomes, and every 1 point increase in PF-10 score was associated with 4% lower odds of impaired physical performance (95% confidence interval 2-7, P = .01) after adjustment. CONCLUSIONS: SF-36, especially PF-10, is a valid surrogate that discriminates low physical performance and physical inactivity in the absence of formal physical function testing in patients on hemodialysis. The routine implementation of the PF-10 in clinical care has important clinical implications for medical management and therapeutic decision-making in patients undergoing hemodialysis.

Rising vs. falling phases of core temperature on endurance exercise capacity in the heat.

PURPOSE: Core temperature (Tc) shows rising (05:00-17:00 h) and falling (17:00-05:00 h) phases. This study examined the time-of-day effects on endurance exercise capacity and heat-loss responses to control Tc in the heat at around the midpoint of the rising and falling phases of Tc. METHODS: Ten male participants completed cycling exercise at 70% peak oxygen uptake until exhaustion in the heat (30 °C, 50% relative humidity). Participants commenced exercise in the late morning at 10:00 h (AM) or evening at 21:00 h (PM). RESULTS: Time to exhaustion was 28 ± 13% (mean ± SD) longer in PM (49.1 ± 16.3 min) than AM (38.7 ± 14.6 min; P < 0.001). Tc before and during exercise were higher in PM than AM (both P < 0.01) in accordance with the diurnal variation of Tc. The rates of rise in Tc, mean skin temperature, thermal sensation and rating of perceived exertion during exercise were slower in PM than AM (all P < 0.05). Dry and evaporative heat losses and skin blood flow during exercise were greater in PM than AM (all P < 0.05). During 30-min post-exercise recovery, the rates of fall in Tc and skin blood flow were faster and thermal sensation was lower in PM than AM (all P < 0.05). CONCLUSIONS: This study indicates that endurance exercise capacity is greater and heat-loss responses to control Tc during and following exercise in the heat are more effective in the late evening than morning. Moreover, perceived fatigue during exercise and thermal perception during and following exercise are lower in the late evening than morning.

Solar radiation and the validity of infrared tympanic temperature during exercise in the heat.

We investigated the validity of infrared tympanic temperature (IR-Tty) during exercise in the heat with variations in solar radiation. Eight healthy males completed stationary cycling trials at 70% peak oxygen uptake until exhaustion in an environmental chamber maintained at 30°C with 50% relative humidity. Three solar radiation conditions, 0, 250 and 500 W/m2, were tested using a ceiling-mounted solar simulator (metal-halide lamps) over a 3 × 2 m irradiated area. IR-Tty and rectal temperature (Tre) were similar before and during exercise in each trial (P > 0.05). Spearman's rank correlation coefficient (rs) demonstrated very strong (250 W/m2, rs = 0.87) and strong (0 W/m2, rs = 0.73; 500 W/m2, rs = 0.78) correlations between IR-Tty and Tre in all trials (P < 0.001). A Bland-Altman plot showed that mean differences (SD; 95% limits of agreement; root mean square error) between IR-Tty and Tre were - 0.11°C (0.46; - 1.00 to 0.78°C; 0.43 ± 0.16°C) in 0 W/m2, - 0.13°C (0.32; - 0.77 to 0.50°C; 0.32 ± 0.10°C) in 250 W/m2 and - 0.03°C (0.60; - 1.21 to 1.14°C; 0.46 ± 0.27°C) in 500 W/m2. A positive correlation was found in 500 W/m2 (rs = 0.51; P < 0.001) but not in 250 W/m2 (rs = 0.04; P = 0.762) and 0 W/m2 (rs = 0.04; P = 0.732), indicating a greater elevation in IR-Tty than Tre in 500 W/m2. Percentage of target attainment within ± 0.3°C between IR-Tty and Tre was higher in 250 W/m2 (100 ± 0%) than 0 (93 ± 7%) and 500 (90 ± 10%; P < 0.05) W/m2. IR-Tty is acceptable for core temperature monitoring during exercise in the heat when solar radiation is ≤ 500 W/m2, and its accuracy increases when solar radiation is 250 W/m2 under our study conditions.

Osteoporosis complication is a risk factor for frailty in females with type 2 diabetes mellitus.

[Purpose] This study aimed to examine the effect of osteoporosis complications on the physical function, frailty in patients with type 2 diabetes mellitus. [Participants and Methods] The participants were 27 female type 2 diabetes mellitus patients aged ≥65 years. Of these, 14 patients had osteoporosis. In order to evaluate the physical function, we measured the lower limb muscle strength, handgrip, gait speed, etc. We performed statistical comparison of both the groups and examined the applicable number of items on the Linda Fried Frailty scale and the correlation by evaluating the physical function. [Results] The lower limb muscle strength of patients with osteoporosis and type 2 diabetes mellitus was significantly lower than that of type 2 diabetes mellitus patients without osteoporosis. Factors of the osteoporosis group that inversely correlated to the Linda Fried Frailty scale included lower limb muscle strength, handgrip, and gait speed. [Conclusion] We found that osteoporosis reduced lower limb muscle strength in type 2 diabetes mellitus patients and was correlated with frailty.

Separate and combined effects of exposure to heat stress and mental fatigue on endurance exercise capacity in the heat.

PURPOSE: This study investigated the effects of exposure to pre-exercise heat stress and mental fatigue on endurance exercise capacity in a hot environment. METHODS: Eight volunteers completed four cycle exercise trials at 80% maximum oxygen uptake until exhaustion in an environmental chamber maintained at 30 °C and 50% relative humidity. The four trials required them to complete a 90 min pre-exercise routine of either a seated rest (CON), a prolonged demanding cognitive task to induce mental fatigue (MF), warm water immersion at 40 °C during the last 30 min to induce increasing core temperature (WI), or a prolonged demanding cognitive task and warm water immersion at 40 °C during the last 30 min (MF + WI). RESULTS: Core temperature when starting exercise was higher following warm water immersion (~38 °C; WI and MF + WI) than with no water immersion (~36.8 °C; CON and MF, P < 0.001). Self-reported mental fatigue when commencing exercise was higher following cognitive task (MF and MF + WI) than with no cognitive task (CON and WI; P < 0.05). Exercise time to exhaustion was reduced by warm water immersion (P < 0.001) and cognitive task (P < 0.05). Compared with CON (18 ± 7 min), exercise duration reduced 0.8, 26.6 and 46.3% in MF (17 ± 7 min), WI (12 ± 5 min) and MF + WI (9 ± 3 min), respectively. CONCLUSIONS: This study demonstrates that endurance exercise capacity in a hot environment is impaired by either exposure to pre-exercise heat stress or mental fatigue, and this response is synergistically increased during combined exposure to them.

Comparison between stair-climbing test and six-minute walk test after lung resection using video-assisted thoracoscopic surgery lobectomy.

[Purpose] Currently, the six-minute walk distance (6MWD) is used to evaluate exercise capacity in people following lung resection for non-small cell lung cancer. However, it is unclear whether the 6MWD can detect changes in cardiorespiratory fitness induced by exercise training or lung resection. Conversely, the stair-climbing test is used frequently for the preoperative evaluation of lung resection candidates. It is considered a sensitive method for detecting changes associated with training, but is not used to evaluate exercise capacity after lung resection. The purpose of this study was to compare the stair-climbing test and the six-minute walk test (6MWT) after lung resection. [Subjects and Methods] Fourteen patients undergoing lung resection completed the stair-climbing test and the 6MWT preoperatively, and one month postoperatively. The postoperative values and the percentage change in the stair-climbing test and the 6MWT were evaluated. [Results] The stair-climbing test results showed a significant deterioration at one month after lung resection; however, a significant change in the 6MWD was not observed. [Conclusion] When compared with the 6MWT, the stair-climbing test was more sensitive in detecting lung resection-induced changes in cardiorespiratory fitness.